Grinding wheel dresser



ADI;il 1949. F. A. MILLER 2,468,096

GRINDING .WHEEL DRESSER Filed Sep t. 11, 194'? s Sheets-Sheet 1 [L I Frank A Miller April 26, 1949. F. A. MlLLER 2,468,096

GRINDING WHEEL DRES SER Filed Sept. 11, 1947 I 3 Sheets-Sheet 2 a woe/MM Frank Ami-11E? u wMaflw April 26, F. A.'MlLLER GRINDING WHEEL DRESSER 5 Sheets-Sheet I5 Filed Sept. 11, 1947 9w .3; mm mwfl QWXIIIIIM m & I

Patented Apr. 26, 1949 UNITED STATES PATENT OFFICE 4 Claims.

(Granted under the act of March 3, 1883. as

amended April 30, 1928; 370 0.- G. 757) The invention described in the following specification and claims may be manufactured and used by or for the Government for governmental purposes without the payment to me of any royalty thereon.

This invention relates to a grinding wheel dresser for attachment to a machine such as a thread grinding machine for dressing the grinding wheel to correspond to a highly accurate template.

In the production of hobs or other similar articles of manufacture on a thread grinding machine, the grinding wheel utilized in such machines must have an accurately shaped contour or cutting edge in order to produce the correct contour on the hob or other article. In the past, much difiiculty has been encountered in producing the contour desired on the grinding wheel to the exacting requirements necessary for production of high quality hobs. The prior art devices utilized for such purpose were somewhat cumbersome and slow of use and the results obtained therefrom were of doubtful accuracy.

Accordingly it is an object of this invention to provide a device adapted to be readily secured to a machine for accurately and quickly dressing a grinding wheel to the contour desired.

Another object of this invention is to provide a grinding wheel dresser for a machine which can be utilized to accurately dress a grinding wheel to a desired contour by simple manipulation of single operating lever.

Another object of this invention is to provide a device for dressing a grinding wheel having adjustable resilient means for follower control.

The specific nature of this invention as well as other objects and advantages thereof will clearly appear from a description of a. preferred embodiment as shown in the accompanying drawings in which:

Fig. 1 is a side elevational view of the grinding wheel dresser.

Fig. 2 is a detail view of the cylindrical bar member.

Fig. 3 is a detail view of the disks utilized to support the cutting diamonds.

Fig. 4 is a top View of Fig. 1 with the cover plate partially broken away.

Fig. 5 is an end view of the tool holder showing the manner of securing the cutting diamonds.

Fig. 6 is an enlarged fragmentary detail View showing the form of the template.

Fig. '7 is an enlarged side elevational detail view of the pin utilized to connect the actuating arm to the bar member.

Fig. 8 is a side elevational view of another connecting pin utilized with the pin shown in Fig. 7 for a similar purpose.

Fig. 9 is a detail perspective view of the spring guide member.

Fig. 10 is a detail view taken along the line III-I0 of Fig. 13.

Fig. 11 is a detail top view of the guide member.

Fig. 12 is a side elevational view of the roller bearing support pin.

Fig. 13 is a view similar to Fig. 1 shown partly broken away to illustrate the mechanism contained therein but with the base member removed.

Fig. 14 is a detail view of the pin on which the block slides.

Fig. 15 is a front elevational view of the block member.

This invention comprises essentially a tool holder mounted on a bar which is arranged for what may be called pantographical movement, the control of such movement being governed by a template. Spring means is provided to maintain a guide member against the template and a lever, which is indirectly secured to the bar, provides the means for moving the tool holder. The grinding wheel dresser is mounted on a suitable base which is adapted to be secured to a machine having a grinding wheel to be dressed.

In Fig. 1 there is shown in assembled relation a grin-ding wheel dresser embodying this invention. The elements of such dresser are mounted on a bracket II) which has a substantially fiatbase portion II. On one end of base portion II there is provided a pair of oppositely disposed upstanding arm-like members I2 and I3. Near the top of arms I2 and I3 there is provided a horizontally disposed hole I4. On the opposite end of base portion II there is provided a pair of upstanding arms I5 and I6, which are substantially rectangular in shape. A horizontally disposed transverse hole I! is provided in each arm I5 and I6 near the lower end thereof.

Bracket I0 is pivotally mounted to a. base member I8 by a pin I9. Base member I8 is provided with an upstanding arm 20 having a transverse hole '2I therethrough near the top of such arm. I-Iole 2I accommodates pin I9 to secure bracket II] to' base member I8. Base I8 has a rearwardly projecting bracket-like member 22 having a rectangular portion 23 in which is provided a threaded hole 24 longitudinally disposed with respect to base I8. The bottom of base I8 has a dovetail portion 25 and such portion along with threaded 3 hole 24 are utilized to mount the grinding Wheel dresser to a thread grinding machine or other machine which can advantageously utilize this invention.

Hole [1 and vertically disposed arms 15 and are provided to support a shaft 26 and shaft 26 in turn slidably supports a block member 21. Block 27 comprises a cylindrical portion 28 having an axial longitudinal hole 29 to accommodate shaft 26. On top of cylindrical portions28 there is provided an integrally formed transversely disposed rectangular top portion 38. Such member has a hole 3| extending therethrough at right angles to hole 29. Longitudinally disposed, diametrically opposed slots 32 are provided in top portion 30 symmetrical with' respect to the vertical axis of cylindrical portion 28. A vertically disposed hole 33 is provided in top portion 30 which is disposed on the vertical axis of cylindrical portion 28; *Slots 32 and hole 33 are provided for'a' purpose t'o' appear later. i On oppo- 'sit"sides of toii portion 38 the're'is mundanetangular recess 35. Each d'fthe's'e recesses -is provided to support a"bal1 "b'aring' as will be-later described, I v 1 Hole 3|- in top portitl n' 38 accommodates a cylindrical bar member 34. On one end of'bar m'mber 3 4 there is provided an-integral square h ed pqr ien... fivideii'in'such'headl In the opposite 'end of' bar 34 thereis, provided another transv'erse hole 38, "theaxis 'of wllich lays inthe sameplane as hole 31-: i A re ta ngularj longitudinally disposedfkeyway 39is provided in bar "34 intersecting thev hole 38. In a proximately the center of bar 34 there 'is'provided'a transversehole 40 which is disposed at right angles to the axis of holes"3'l a'nd'38.

When bar 34 is inserted in hole 3| and hole 40 aligned with slots 32, a pin 4| is inserted in hole 4(fthrough slot 32. Pin 4| is of such' length that a sufiicient amount projects from each side'of ftjopportion 38 ,ir1' order that a ball bearing 42 may be mounted thereon. Each. of the ball bearings 42 rest within' .'r p'ective. recesses 35. "On

top or portion '30 wasps rotatably supported a ball bearing. 43' .on a vertically disposed pin 44 "A plate 45 is securedlto'the top of upstanding armsi'l5 and I6 of bracket'flfl by means of screws L46 an'dldowel pin's '41. Arectangular cut-out por- 'tioril' '48. .-.is p'rovided in the center i of such plate an v be i r .3 f nte t surface 149 s cutout..- Aiplate 50 is similarly secured on top of Template 53 is secured to arms and l6by screws55. "Projectio'n54 of'template 53 is shaped :to-conform to the contour desired to be produced .on- -t-hegrinding wheel of th machineto which' this fixture-isfto-be attached. In the preferred application -of-this invention; the projection 54 tal ies the shape of a tooth 'on'a threading hobas shown in Fig. 6.

A transverse. hole 31. is pic- A'cover plal'l-e 58 is -placed over plates 45fc58 'Atool holder? etangular bar 9:1..dsr securedetoilthe.iouter end..Jcf

and template 53. Such plate has a raised boss 5'! in the center near the right-hand edge thereof and a vertically disposed hole 58 is provided through such boss and plate 56 in which is inserted a pin 59. Such pin is secured within hole 58 by a press fit.

f An actuating arm fifl'is pivota'llywmounted on pin 59 for actuation of bar 34, as will be later explained. A thumb screw I23 threaded into the end of pin 59 secures arm 60 to such pin. A vertically/disposed hole 6| in arm 50 accommodates pin-59. Arm 60 comprises essentially a rectangular bar having one end 62 disposed at an acute angle with respect to the body thereof. A handle portion 63is secured, preferably by welding; to bent end 52 and such handle is disposed upwardly, as shown in Fig. 1, to facilitate manipulation th'erepff A portion of the other end 64 of arm an is cylindrical and a cylindrical bore 65 is provided in arm 60 from end 64 which extends a subst'antia'l distancemlntmsuchcarm;r:and the enteringendaof such bore isnprovided with.

te'rnai threads-"61.: Amectangulanrecess 66 having rounded ends? communicates with: bore 5 the underside of arm 60.

CConnectiontbetween arm60 andfibarzail 15 .made principallyrbywwo: pins; EQZBJIEKCGQ'JZ'. PH .5 c m-- rises LtWO cylindrical: portions: 'lfl ..and -r' l-s pa- 5 from rated: by "Jan integral;masherelika m mber-.112-

The lower end of cylindrical portion 18 has' ;a --rectaligulan: notch C73 :andisuizh endiisx nserted in hole '38 *ofitbaltriflz: key dhinsel tg d. ni ke wy 3'9 likewise :enga'gesfnotch' Flt-thereby lockin Pi .6 a-a'gain-st turning'siniban 34: ;.A;scr.ew 5.:th ead d into Ir hol'e 124:securesizpinnw:torbara34.1.1

I A guide Tmemberil lisis'i'placedromthext indr portion ll ofpintfid: *iGllideamember su stanti'ally-a-..rectangtu1aremember havingza rou dediendr 111;: mzvertically:disposedehole 18i SilCh guide. member:caccbinmodatesiiportion;a'l'l of pin 69. CornersrH andv8fl.1orzguidezmember 16am preferably tipped:Withxcarbid'e.:to better.-;res.i. wear; A.lverticailyimspbsedzrectangular inotch, 8 I

.xis-tprovidedzin the troundedt end 1.! yfor a purp .to 'app'eanzlaterr or? 1,.

, I ..cylindricalcollarlike integral:bearingcmemben824;..010 the under.- side'of" such ..co1lal::-lil e member there .is inte rally formed anaxial threadedlstudelike member. 8.3. such stud-like .memb'er e ngages a. threaded recess84 provided onthletop of 42111.69; Collar-like member 82 thus secures guidejflfi," Upperi'end 85 of .pin :68..'is.of .slig h'tly. reduced; diameter and intermediate. v.sil :h;e;flc1f pontign iian'd collar-llke member '82 a .rollei: bearing- 86 is-placedthereon; Roller bea'ringiflicontacts the sidewalls ofre'cessfifi providedin arm"60.-' A'spring guide member 81"comprising*a blockportion 88'having a' vertically disposed h'ole 89therein' 'has a rearwardly facing stud 90, hole' tsin such block accommodating end 85'of pin StudxSIl mounts one end of a spring 8| which is inserted'r'in bore 65of arm 60. Asc'rew 92tiirne'd into threaded end 61 of arm 60 retains a ball I28 whichfiseats springQl Withinbore 65:"rGuide: memberlfi is keyed to pin 69 by-al 'keyfl Keya93len'gages5a suitable rectangular notch ".9 rovidedpin .the washer-like member 12 ofs plni. :JzSuch key is secured to guide 16.2 .55'13 screw 295.;- Thus. guide membemifisis, prevented fromrrotating .on ,pin 69 and connectionszbetweenarm .60 and 'barg34. is

. slsentiualiyicomprising a leobar 34. Tool holder 96 isaprmddednwitl'rzcylindrical ends 98 and 99 and end 98 is inserted into hole 31 of bar 34 and is positioned therein by a screw I which is screwed into a threaded cylindrical recess IOI provided in the end of cylindrical end 98. Tool holder 96 is locked by a set screw I29. Too-l holder 96 is prevented from turning in hole 3! by keys I02. Keys I02 are placed in a keyway I25 provided in the end 98 of bar 91 of tool holder 90.

The holder for securing the cutting diamonds comprises two discs I04 and I05. Disc I04 is provided with two radially disposed rectangular grooves I09 and than 90 degrees. Disc I is provided with corresponding grooves I28 and I21 which are however of V shape. A rectangular vertically disposed notch I08 is provided in each of such discs which are engaged by key I30, which lies in a keyway I03 of bar 91 to lock such discs to bar 91. Tool bits I09 and I09 are respectively inserted in grooves 806 and I0! and each of such tool bits preferably has a diamond I I0 in the point thereof. Bits I09 and I09 are secured within their respective grooves by a plurality of screws I I I which secure disc I05 to disc I04. A screw II2 having a knurled cylindrical head portion I I3 is threaded into a hole H4 in cylindrical end 99 of holder 98 to secure discs I04 and I05 to holder 96 and to permit rapid removal thereof for resetting or replacement of tool bits I09 and I09.

To dress a grinding Wheel of a threading machine (not shown) the grinding wheel dresser is mounted on the machine by means of the dovetail 25 of base member I8. Guide member I6 is maintained against projection 54 of template 53 by the action of spring 9| bearing against pin 68. When handle or lever 63 of arm 60 is rotated about pin 59 in either a clockwise or counterclockwise direction, arm 90 is forced to pivot about pin 59, thus forcing block member 21 to slide on shaft 26 in a corresponding direction. This forces guide member 15 to slide along projection 54. As has been mentioned, projection 54 is shaped to correspond to a tooth being produced on a threading hob.

spending upon the direction of rotation of lever 63, the corners I9 or 80 will follow the contour of projection 54 of template 53. For example, when lever 63 is rotated in a clockwise direction, block 2! will be forced to move downwardly as shown in Fig. 4 and corner 80 of guide I6 passes over a flat front portion I I8 of projection 54. Tool bit'I09 will produce a cut on a wheel II5 corresponding to such flat portion. When corner 80 reaches the end of such fiat portion, corner 80 will be'forced down a sloped side II9 of projection 54 thereby producing a corresponding slope I20 on grinding wheel H5, spring SI of arm 60 maintaining guide IE in intimate contact with template 59 at all times. To reproduce sloped side I2I of projection 54, lever 63 is rotated in a counterclockwise direction which forces guide I6 to retrace the path just taken and then corner I9 will be forced down slope I2I thereby producing a corresponding slope I22 on wheel II5. The tool bit I09 dresses the wheel on the opposite side of grinding wheel H5. Bearings 42 and provide relatively frictionless bearing support for bar 34 and block 21, thereby also insuring long life and optimum accuracy in such bearing.

From the foregoing description it is clearly apparent to those skilled in the art that there is here provided a grinding wheel dresser that quickly and accurately shapes a grinding wheel to any desired contour, the contour of such grinding wheel having sides disposed at 90 de- I01 disposed at somewhat less I face of such wheel. The tool bits I09 and I09 may be conveniently set to the desired distance from the face of tool holder 96 by means of a suitable gage and when once set will accurately dress any number of grinding wheels to the exact contour of template 53. It will also be appreciated that the grinding wheel dresser herein described is of sturdy construction yet light in weight enabling the operator to readily mount such dresser on any machine for dressing of the grinding wheel plate. The contour of the grinding wheel can be readily changed to any desired shape by merely replacing template 53 with one having the desired contour.

I claim:

1. A grinding wheel dresser for a machine tool having a grinding wheel, said grinding wheel dresser comprising, a bracket, said bracket having a pair of opposed upstanding arms arranged to support a shaft, a block member slidably mounted on said shaft, a tool holder slidably mounted in said block member for transverse movement with respect to said shaft, a cover plate secured on top of said bracket arms, a lever-like member pivotally mounted on said cover plate, means connecting said lever-like member with said tool holder, said tool holder arranged to be simultaneously moved in a transverse or longitudinal direction with respect to said shaft by said lever-dike member, a template secured to said bracket, guide means associated with said tool holder and arranged to contact said template, and resilient means maintaining said guide means in intimate contact with said template, said template governing the movement ofsaid tool holder whereby the contour of said template is reproduced on the grinding wheel.

2. A grinding wheel dresser for a machine tool having a grinding wheel, said grinding wheel dresser comprising, a bracket, a shaft rigidly mounted in said bracket, a block member slidably mounted on said shaft, a tool holder slidably mounted in said block member for transverse movement with respect to said shaft, a lever pivotally mounted on said bracket, said lever having an arm disposed beyond the pivot point of said lever, said arm being provided with an elongated recess therein, and a pin connectin said lever with said tool holder, said elongated recess accommodating one end of said pin whereby rotation of said lever moves said tool holder in any desired direction in a horizontal plane.

3. A grinding wheel dresser for a machine tool having a grinding wheel, said grinding wheel dresser comprising, a bracket, a shaft rigidly mounted in said bracket, a block member slidably mounted on said shaft, a tool holder slidably mounted in said block member for transverse movement with respect to said shaft, a lever pivotally mounted on said bracket, said lever having an arm disposed beyond the pivot point of said lever, said arm having an axial recess therein communicating with a transverse elongated recess, a pin connecting said tool holder with said lever, one end of said pin being inserted in said elongated recess, a spring mounted within said axial recess, and means to govern the movement of said tool holder when said lever is rotated, said spring being arranged to maintain said tool holder against said governing means.

4. A grinding wheel dresser for a machine tool having a grinding wheel, said grinding wheel dresser comprising, a bracket, a shaft rigidly grees or less from the mounted in said bracket, 9. block member slidably mounted on said shaft, a tool holder slidinserted in said elongated recess, a spring 1 mounted within said axial recess, a template secured to said bracket, and a guide member mounted on said pin, said guide'member being disposed opposite said template, said template file of this patent: 0

determining the path 01' movement of said tool holder when said lever is rotated, said spring arranged to maintain said guide member against said template.

FRANK A. NIILLER.

REFERENCES CITED The following references are'of record in the UNITED STATES PATENTS Number. v.

a Name Date 1,592,076 Bugbee July 13, 1926 $415,010 H111 Jan. 28, 1947 

